Algebraic torus

We initiate the study of certain families of L-functions attached to characters of subgroups of higher-rank tori, and of their average at the central point. In particular, we evaluate the average of the values L( 2 1 , chi a )L( 21 , chi b ) for arbitrary ...

Polish Acad Sciences Inst Mathematics-Impan2024

On algebraic twists with composite moduli

We study bounds for algebraic twists sums of automorphic coefficients by trace functions of composite moduli. ...

Springer2023

ALGEBRAIC TWISTS OF GL3 x GL2 L-FUNCTIONS

Vignesh Arumugam Nadarajan

We prove that the coefficients of a GL3 x GL2 Rankin-Selberg L-function do not correlate with a wide class of trace functions of small conductor modulo primes, generalizing the corresponding result of Fouvry, Kowalski, and Michel for GL2 and of Kowalski, L ...

Johns Hopkins Univ Press2023

Algebraic twists of GL(2) automorphic forms

In this thesis we consider the problem of estimating the correlation of Hecke eigenvalues of GL2 automorphic forms with a class of functions of algebraic origin defined over finite fields called trace functions. The class of trace functions is vast and inc ...

EPFL2023

Hopf algebras and Hopf-Galois extensions in infinity-categories

Aras Ergus

In this thesis, we study interactions between algebraic and coalgebraic structures in infinity-categories (more precisely, in the quasicategorical model of (infinity, 1)-categories). We define a notion of a Hopf algebra H in an E-2-monoidal infinity-catego ...

EPFL2022

Covers Of Rational Double Points In Mixed Characteristic

Javier Alonso Carvajal Rojas

We further the classification of rational surface singularities. Suppose (S, n, k) is a 3-dimensional strictly Henselian regular local ring of mixed characteristic (0, p > 5). We classify functions f for which S/(f) has an isolated rational singularity at ...

2021

Computing Cyclic Isogenies between Principally Polarized Abelian Varieties over Finite Fields

Marius Lorenz Vuille

Abelian varieties are fascinating objects, combining the fields of geometry and arithmetic. While the interest in abelian varieties has long time been of purely theoretic nature, they saw their first real-world application in cryptography in the mid 1980's ...

EPFL2020

Isogeny graphs of ordinary abelian varieties

Dimitar Petkov Jetchev, Benjamin Pierre Charles Wesolowski, Ernest Hunter Brooks

Fix a prime number l. Graphs of isogenies of degree a power of l are well-understood for elliptic curves, but not for higher-dimensional abelian varieties. We study the case of absolutely simple ordinary abelian varieties over a finite field. We analyse gr ...

Springer Heidelberg2017

Examples of algebraic groups of type G (2) having the same maximal tori

Ting-Yu Lee

Answering a question of A. Rapinchuk, we construct examples of non-isomorphic semisimple algebraic groups H (1) and H (2) of type G (2) having coherently equivalent systems of maximal k-tori. ...

Maik Nauka/Interperiodica/Springer2016

Central Subalgebras Of The Centralizer Of A Nilpotent Element

Let G be a connected, semisimple algebraic group over a field k whose characteristic is very good for G. In a canonical manner, one associates to a nilpotent element X is an element of Lie(G) a parabolic subgroup P - in characteristic zero, P may be descri ...

American Mathematical Society (AMS)2016

The xi-stability on the affine grassmannian

Zongbin Chen

We introduce a notion of xi-stability on the affine grassmannian (SIC) for the classical groups, this is the local version of the xi-stability on the moduli space of Higgs bundles on a curve introduced by Chaudouard and Laumon. We prove that the quotient ( ...

Springer Heidelberg2015

Subgroups Of Simple Algebraic Groups Containing Regular Tori, And Irreducible Representations With Multiplicity 1 Non-Zero Weights

Our main goal is to determine, under certain restrictions, the maximal closed connected subgroups of simple linear algebraic groups containing a regular torus. We call a torus regular if its centralizer is abelian. We also obtain some results of independen ...

Springer Verlag2015

Algebraic Trace Functions Over The Primes

We study sums over primes of trace functions of l-adic sheaves. Using an extension of our earlier results on algebraic twists of modular forms to the case of Eisenstein series and bounds for Type II sums based on similar applications of the Riemann hypothe ...

Duke Univ Press2014

Embeddings Of Maximal Tori In Orthogonal Groups

Eva Bayer Fluckiger

We give necessary and sufficient conditions for an orthogonal group defined over a global field of characteristic not equal 2 to contain a maximal torus of a given type. ...

Annales Inst Fourier2014

Spaces With Noetherian Cohomology

Jérôme Scherer

Is the cohomology of the classifying space of a p-compact group, with Noetherian twisted coefficients, a Noetherian module? In this paper we provide, over the ring of p-adic integers, such a generalization to p-compact groups of the Evens-Venkov Theorem. W ...

Cambridge University Press2013

On the Reduction of Points on Abelian Varieties and Tori

Let G be the product of an abelian variety and a torus defined over a number field K. Let R-1, ..., R-n be points in G(K). Let l be a rational prime, and let a(1), ..., a(n) be nonnegative integers. Consider the set of primes p of K satisfying the followin ...

2011

Capacities, Systoles and Jacobians of Riemann Surfaces

Björn Mützel

To any compact Riemann surface of genus g one may assign a principally polarized abelian variety (PPAV) of dimension g, the Jacobian of the Riemann surface. The Jacobian is a complex torus and we call a Gram matrix of the lattice of a Jacobian a period Gra ...

EPFL2011

Homotopic Hopf-Galois extensions: foundations and examples

Kathryn Hess Bellwald

Hopf-Galois extensions of rings generalize Galois extensions, with the coaction of a Hopf algebra replacing the action of a group. Galois extensions with respect to a group

G

are the Hopf-Galois extensions with respect to the dual of the group algebra of ...

2009

Two variants of the support problem for products of abelian varieties and tori

Let G be the product of an abelian variety and a torus defined over a number field K. Let P and Q be K-rational points on G. Suppose that for all but finitely many primes p of K the order of (Q mod p) divides the order of (P mod p). Then there exist a K-en ...

2009

Related publications (22)

Isogeny Problems with Level Structure

Tako Boris Fouotsa

2024

Toroidal families and averages of L-functions, I

Polish Acad Sciences Inst Mathematics-Impan2024

On algebraic twists with composite moduli

We study bounds for algebraic twists sums of automorphic coefficients by trace functions of composite moduli. ...

Springer2023

ALGEBRAIC TWISTS OF GL3 x GL2 L-FUNCTIONS

Vignesh Arumugam Nadarajan

Johns Hopkins Univ Press2023

Algebraic twists of GL(2) automorphic forms

EPFL2023

Hopf algebras and Hopf-Galois extensions in infinity-categories

Aras Ergus

EPFL2022

Covers Of Rational Double Points In Mixed Characteristic

Javier Alonso Carvajal Rojas

2021

Computing Cyclic Isogenies between Principally Polarized Abelian Varieties over Finite Fields

Marius Lorenz Vuille

EPFL2020

Isogeny graphs of ordinary abelian varieties

Dimitar Petkov Jetchev, Benjamin Pierre Charles Wesolowski, Ernest Hunter Brooks

Springer Heidelberg2017

Examples of algebraic groups of type G (2) having the same maximal tori

Ting-Yu Lee

Answering a question of A. Rapinchuk, we construct examples of non-isomorphic semisimple algebraic groups H (1) and H (2) of type G (2) having coherently equivalent systems of maximal k-tori. ...

Maik Nauka/Interperiodica/Springer2016

Central Subalgebras Of The Centralizer Of A Nilpotent Element

American Mathematical Society (AMS)2016

The xi-stability on the affine grassmannian

Zongbin Chen

Springer Heidelberg2015

Subgroups Of Simple Algebraic Groups Containing Regular Tori, And Irreducible Representations With Multiplicity 1 Non-Zero Weights

Springer Verlag2015

Algebraic Trace Functions Over The Primes